Chelsea Thornton was being held at Orleans Parish Prison. New Orleans police said she admitted in a recorded interview to shooting her 3-year-old son and drowning her 4-year-old daughter in a bathtub Wednesday afternoon.

Police said the boy was shot with a semi-automatic handgun. In a court record, police said Thornton told investigators that the girl was drowned after the gun failed to fire again.

Investigators said she then left the home, in the 3300 block of Audubon Court, and took a bus to a hospital because she was suffering from stomach pains and a headache.

The children's grandmother found the lifeless bodies of the toddlers about 5:30 p.m. and called for help. No one else was at the home, officials said.

One investigator could only describe it as a "terrible, terrible tragedy."

NOPD did not release a possible motive for the murders and asked anyone with information on the suspect or crimes to call Crimestoppers at 504-822-111.